1. Field of the Invention
The present invention relates generally to the field of data processing. More specifically, the present invention relates to a system and method for selective encryption of electronic messages and data.
2. Background Information
With advances in integrated circuit, microprocessor, networking and communication technologies, an increasing number of devices, in particular, digital computing devices, are being interconnected. This increased interconnectivity of computing devices has laid the groundwork for a communication infrastructure particularly well suited for electronic communications between such computing devices. More specifically, the increased interconnectivity of computing devices has led to the near ubiquitous adoption of electronic mail (email) as a standard mode of communication.
In the past, electronic mail communications were limited to the exchange of text-based messages between a relatively small populous. Over time, however, email applications and associated communications protocols have become increasingly sophisticated enabling more complex messages to be exchanged between larger numbers of individuals. For example, in addition to enabling the exchange of simple text-messages, many modern day email clients allow users to exchange complex, multipart MIME (Multipurpose Internet Mail Extensions) encoded files as well as a wide variety of binary attachments. Furthermore, with the introduction of web-based email clients that utilize World Wide Web protocols, such as the hypertext transmission protocol (HTTP) for the exchange of messages, access to email has become even more prolific.
Unfortunately, however, with increased email accessibility has come the need for improved security with respect to transmission and storage of messages and data. For example, although many existing email servers attempt to store email messages in a secure manner through techniques such as encryption, the access information needed to decrypt encrypted messages is typically co-located on the same server as the stored messages. Accordingly, anyone who is able to gain access to the storage server, whether it may be a system administrator or an unscrupulous hacker, will have access to the encrypted messages as well as access to the information needed to decrypt those messages. Thus, it should be readily apparent, that by storing the access information necessary to gain access to encrypted data on the same device as the encrypted data itself, the data may be susceptible to unauthorized viewing by anyone who is able to gain access to the storage server, whether sanctioned or otherwise. Furthermore, although many mail servers store secure messages on behalf of senders, even a larger number of mail servers store unsecured messages (and data) on behalf of senders. Accordingly, in the event that an unauthorized access did occur on a message storage server, it may be very difficult for the server operator to prove that a particular message or file was not accessed without authorization.